Self-inking hand stamp

ABSTRACT

A self-inking hand stamp includes a novel positively indexing, quick-settable character band printing unit structure and a novel inking structure, as well as a simple, rugged and durable arrangement of parts for extended life in hard usage.

El lisqn et al.

[5 1 s am-1011:1190 114m) STAMP '76 Inventors: Lynn,E.,= ElliSon, 476Gdlf Rd.;

Charles 1). Ellison, 297 s. Virginie 6 St., both of Crystal Lake, lll.60014 22 Filed: v Mar. 20, 1972 211 Appl. No.5 23 ,024

[5 2l U.S.'Cl. 101/333,101/103 51 1111.01 ..B41r1/s0 [58} Field ofSearch; 101/103, 104, 105,

v j I A self-inking hand stamp mcludes a novel positively [56]"References Cited I UNITEDSTATES'PATENTS 3,241,482 4 3/196 Keck;

lo l l entencled life 111 hard usage.

8/1929 Childs... 101/103 1,226,648 5/1917 ,Elhs", ..101/1o3 1,134,9504/1915 Folgeretal 101/103 3,380,378 4/1968 Edwards et al......'..10l/l03X 2,096,340 1'0/1937 1,371,232 3/1927 Prirndry Examiner--Robert E. Pulfrey Assistant Examiner-E. M. Coven Attorney-Carlt0nHill et a1.

[57 ABSTRACT indexing, quick -settable character band printing unit"structure and a novel inking structure, as well as a simplerugged'anddurable arrangement of parts .i'or

16 013161;,11 Drawing'Figures I SELF-INKING HAND STAMP This inventionrelates to self-inking hand stamps, and is more particularly concernedwith such hand stamps especially suitable for use in marking merchandisepackages in supermarkets and the like.

Hand stamps of the character indicated as heretofore provided have hadvarious deficiencies, some of which are points of excessive wear so thatthe useful life is short, complexities of structure which render theunits costly, difficulties in supplying ink to the ink pads, difficultmanipulation of the character-carrying bands of the printing heads orunits, inefficient character registration, tendency for thecharacter-carrying bands to drift in use.

An important object of the present invention is to overcome theforegoing and other disadvantages, defects, inefficiencies,shortcomings, deficiencies and problems in prior structures in a new andimproved self-inking hand stamp, as will hereinafter become apparent.

Another object of the invention is to provide a new andimprovedself-inking hand stamp of rugged, efficient, simple and durableconstruction. v

A further object of the invention is to provide a new and improvedself-inking hand stamp which is smooth in operation and has a minimumnumber of relatively moving operating parts.

Still another object of the invention is to provide a new and improvedhand stamp of the character indicated which eliminates pressure wearpoints.

Yet another object. of the invention is to provide a new and improvedefficiently operating printing unit structure for hand stamps. I

A still further object of the invention is to provide new and improvedindexing means for the printing units of hand stamps.

A yet further object of the invention is to provide a new and improvedinking device for self-inking hand stamps.

Other objects, features and advantages of the invention will be readilyapparent from the following description of a preferred embodimentthereof, taken in conjunction with the accompanying drawings, althoughvariations and modifications may be effected without departing from thespirit and scope of the novel concepts embodied in the disclosure, andin which:

FIG. 1 is a front elevational view of a self-inking hand stamp embodyingfeatures of the invention;

FIG. 2 is a side elevational view of the hand stamp of FIG. 1;

FIG. 3 is a fragmentary sectional detail view taken substantially alongthe line III-III of FIG. 2;

FIG. 4 is an enlarged fragmentary sectional detail view takensubstantially along the line IV-IV of FIG.

FIG. 5 is a side elevational view of the printing unit of the handstamp;

FIG. 6 is a fragmentary sectional view of one of the character-carryingbands, similar to FIG. 4 but relaxed as disassembled from the printingunit or head;

FIGS.v 7 to 10, inclusive, are illustrativeside elevational viewsshowing various positions of the inking device in the course ofoperation of the hand stamp, the views being taken substantially alongthe line VII-VII of FIG. 1; and r s FIG. 11 is a perspective view of theinking device showing the ink pad in its open position for applicationof ink thereto.

A self-inking hand stamp embodying features of the invention, asillustrated in FIGS. 1 and 2 comprises a main body frame 15 of generallyinverted U-sahped structure having respective coextensive spaced legvertical side bars 17 connected by a head bar 18 and having there lowerends fixedly secured to a base plate 19 having therethrough acentralclearance opening 20 between the legs, and carrying elastomericcushioning pads 21 on its lower face.

Mounted on and vertically reciprocable relative to the body frame is aprinting unit actuating frame 22 of inverted U-shape having oppositecoextensive arms 23 which are spaced apart slightly greater than theframe bars 17 so as to be freely reciprocably movable verticallytherealong and are desirably of the same width, being connectedintegrally by a head bar or web 24. Means for normally biasing the frame22 upwardly relative to the frame 15 comprise a coiled compressionspring 25 thrusting at its lower end against an upwardly projecting stem27 centrally fixed on the head bar 18 and projecting into a tubularspring housing 28 fixed centrally on and opening downwardly from thehead bar 24 and provided. at its upper end with a blind end shoulderagainst which the upper end of the spring 25 thrusts. In addition, thetubular member 28 may serve as a handle for manipulating the hand stampand be equipped for this purpose with a suitable head knob 29. Ifpreferred, of course, the frame 22 may be employed as a handle, withdigital pressure applied to the head bar 24 in depressing the printingframe against bias of the spring 25.

Means are provided for guiding the arms 23 along the bars 17 and forsupporting a printing unit 30 to be actuated reciprocably with theprinting frame 22. For this purpose, a guide pin 31 extends throughrespective coextensive vertical guide slots 32 in the frame bars 17 andis connected to the respective arms 23 by extending through the lowerportions thereof, being connected against displacement by meansofresilient snap spring retaining washers 33 connected into terminal endannular grooves in the projecting end portions of the pin. Spacedupwardly from the pin 31 are respective guide studs 34 fixed to the arms23 and extending inwardly in coaxial alignment through the verticalguide slots 32.

Replaceable mounting of the printing unit 30 within the body frame 15 ina manner to be operated reciprocably in straight line vertical manner bymeans of the printing frame 22 is effected by means of the pin 31 andthe studs 34. Accordingly, the pin 31 extends as a shaft in supportingrelation through spaced vertical upwardly extending arms 35 of agenerally U-shaped printing unit frame provided on lower portionsthereof above a rigid integral connecting bridge bar 37 with coaxiallyaligned bearing apertures 38 (FIG. 5) through which the shaft pin 31extends in supporting relation. For rigidity the arms 35 are generallyoutwardly channel-shaped and at their upper ends receive the inner endportions of the studs 34 cooperating with the shaft 311 to hold theprinting unit frame in stable, vertical, centered working relationwithin the body frame 15.

Except for certain improvements, as will be explained, the printing unit30 is similar to customary units of this type. including rubbercheractenearrying bands 39, in this instance five, mounted on and aboutthe bar 37 at the lower end of the unit and about respective adjustmentwheels 40 at the opposite end of the unit each provided with a knurlededge digitally engageable adjustment flange of a diameter to projectsufficiently beyond printing characters 41, such as numbers, punctuationmarks or letters in series on the outer faces of the bands to enableconvenient belt adjusting rotation of the wheels without contacting thecharacters by the manipulating fingers. Coaxial individually rotatablemounting of .the wheels 40 is effected on a shaft 42 secured fixedly toand between the upper end portions of the arms 35.

Means are provided for not only efficient positive adjustment driving ofthe belts or hands 39 by the wheels 40, but also effective indexing andretention of the bands in adjusted positions thereof. To this end, theendless bands 39 are desirably molded from an elastomer such as neopreneof 40-45 durometer and mounted on the printing unit under slighttension. Elasticity of the respective bands is improved by providingfairly deep transvrese grooves 43 between the relatively stiffer areasof the bands providing the characters 41 which have flat face planes.The character areas are thus separated by relatively flexible elasticintegral webs 44, which are preferably molded in a slight inside concaveoutside convex form longitudinally. Between the webs the back faces ofthe respective bands are provided with traction means desirablycomprising transverse serration-like resilient rib teeth 45 which aredimensioned to mesh with and are complementary to similar transverserigid rib teeth 47 on the drum perimeters of the wheels 40. This effectsa fairly positive drive relationship between the wheels and bands andeliminates any need for backing on the bands, enabling a smoother,freer, easier adjustment manipulation of the bands through the wheels41.

For indexing, a novel cooperative relation is provided between theprinting unit frame bar 37 and the bands 39. As is customary, the bar 37provides a rigid thrust backing for the character areas of the bands toenable applying printing impressions of the printing characters 41aligned on the bar onto objects against which impressed by thrusting theprinting end of the printing unit through the clearance opening 20 inthe base 19.

For utmost rigidity, the bar 37 has spaced parallel reinforcing flanges48 (FIG. 4,). For indexing efficiency, the bar 37 is provided withrelatively small radius side edge indexing shoulders 49 which areproperly spaced to register with the respective webs 44 which connecteach of the character areas aligned with the thrust face of the bar 37with the adjacent character areas in each instance. By reason of theslight tension under which the bands 39 are maintained, the web areas 44in engagement with the indexing shoulders 49 are slightly stretched, aswill be apparent on comparison of FIGS. 4 and 6, whereby the relativelystiffer character areas at each end of each of the stretched web areas44 is pulled toward and relatively hugs the bar at each side of each ofthe shoulder ribs 49 and resists drifting of the respective bandlongitudinally thereof, whereby the character area in printingorientation on the bar 37 will remain in proper alignment with all ofthe other character areas in the printing'orientation until deliberatereadjustment of the respective bands is effected by manipulation of theadjustment wheels 41.

Further assistance in the printing character indexing and retention isafforded by the separation between the areas of gripper teeth 45 at thebacks of the webs 44, so that there is an inherent, readily sensiblydetectable snap-on grabbing of the respective web areas 44 onto theshoulder 49 at each end of each of the character areas as the respectivebelt is longitudinally motivated to move a character area across one ofthe shoulders and into position on the thrust face of the bar 37. Notonly does the relatively greater stiffness of the character areacontribute to this action, but the gripping teeth 45 on the back of suchcharacter area provides a mild frictional resistance to movement of thecharacter area across the shoulder so that immediately on passing fromthe shoulder there is a momentary relief of the resistance, sensiblyindicating that the selected character area has been moved into printingposition. This feature is enhanced by providing the thrust face of thebar 37 with an inward depression 50 longitudinally between the shoulders49, within which the gripper teeth 45 of the printing character area arereceived. Through this arrangement the teeth 45 of the imprintingcharacter area assist in the detenting and also in the retention of therespective character band against longitudinal drift.

The depression 50 also enables slight inward yielding for marking onuneven surfaces, or angular or tilted surfaces.

Self-inking means are provided automatically operative to apply ink tothe printing characters aligned along the bar 37. According to thepresent invention, such means comprise an inking device 51 constructedand arranged to move automatically into inking position when theprinting unit 30 is in retracted position within the body frame 15 andto move automatically into clearance relation to the printing unit whenthe printing unit is actuated into printing position by depressing theprinting frame 22 relative to the body frame 15. Further, the inkingdevice 51 is constructed and arranged for greatly facilitating supplyingit with ink. To this end, the inking device 51 (FIG. 11) comprises apair of body side plates 52 of identical, coextensive construction inallochiral spaced parallel relation, desirably of generally rectangularoutline, slightly longer in one face direction than in the otherdirection and rigidly connected together along one of their alignedshorter edges by a pair of spaced parallel coextensive rods 53 and 54,one of which is fixedly secured adjacent to one comer area and the otherto the other corner area adjacent to such edge of the plates.

In addition to serving as frame connectors for the side plates, the rods53 and 54 provide means for supporting an ink pad 55. Such pad comprisesa suitable panel of ink-carrying and applying material. Commonly anabsorbent felt pad has been used for this purpose, but significantlyimproved results are obtained by means of a pad of suitable thickness ofinterconnected cellular resilient foam material such as foam latex,polyvinylchloride foam, or the like having minutely dimensioned porosityso as to be possessed of large ink capacity but strong and fairlyuniform and adequately dense but porous applicator surface. It has beenfound that such material provides a continuously uniform application ofink to the printing characters as long as there is any'ink on and in thepad.

For'supporting the ink pad 55 operatively, an ink pad tray having narrowoverhanging pad retaining flanges 58 along opposite edges is mountedfixedly on a panel 59 arranged to be carried by the rods 53 and 54. Thetray 57 may be formed from relatively thin sheet metal and the panel 59from heavier gauge sheet metal and the two members secured together asby means of spot welding.

In order to facilitate inking of the pad 55, the supporting panel 59 isarranged to be hingedly connected to one of the supporting rods andlatchingly engaged with the other of the rods. To this end, thesupporting panel 59 is dimensioned to be receivedbetween the margins ofthe side plates 52 having the rods 53 and 54 and with opposite marginsof the panel 59 engageable with the respective rods. Along the edgedefining one of the panel margins it is provided with means for hingedlysecuring it to one of the rods, in this instance the rod 53. Suchhinging means desirably comprise a pair of coextensive spaced hinge curlflanges 60 engaging partially around the rod 53 sufficiently to retainthe rod between the hinge flanges and the adjacent edge of the tray 58,enabling pivotal swinging of the inking pad supporting panel between anopen, extended position as shown in FIG. 11 and a closed, operatingposition as shown in FIGS. 1 and 7. In the operating position, a pair ofsnap-latch flanges 61 separated by a handle flange 62 along the freemargin of the plate 59 engage in frictional digital pressure-releaseablerelation with the rod 54. Reinforcement of the latching margin iseffected by reinforcing ribs 63 extending normal to the flanges 61 butclear of the adjacent edge of the tray 57. Through this arrangement, theink pad carrier 59 is adapted to be manipulated by means of the handleflange 62 between the open position and the closed position with theretaining spring latch flanges 61 effec-- tively retaining the carrierin the operating positionon and between the rods 53 and 54 and enablingready opening of the pad by snapping the flanges 61 away from the rod 54when it is desired to gain access to the ink pad 55 for inking purposes.

Mounting of the carriage of the inking device 51 is in a manner to swingautomatically between inking and clearance positions relative to theunit 30 responsive to movements of the printing frame 33 betweenretracted and printing positions. For this purpose, the sides 52 arepivotally mounted on the side bars 17 between them and the unit 30 to beactuated by a coupling with the shaft 31. Hence, the side plates 52 areprovided with coaxially aligned bearing apertures 63 eccentricallyadjacent to the long edge nearest the, frame bar 54 and through whichare engaged respective headed pintles 64 fixed upon the inner sides ofthe respective side bars 17 so that the device 51 is freely pivotallymovable between the inking position shown in FIG. 7 and the printingunit clearing position shown in FIG. 10, also exemplified in FIG-ll.Operative coupling with the shaft 31 is effected through respectivealigned, coextensive generally dog leg control cam slots 65 in the endplates 52 adjacent to the free edges of the plates and with their endsadjacent to the longitudinal edges of the plates. Their spacing andrelationship to the eccentric pivot bearing apertures 63 is such,together with theirparticular cam contour, that when the printing unit30 is in its retracted position the inking device 51 is drawn inwardlyto press the ink pad 55 lightly against the printingly orientedcharacters along the printing pressure bar 37 as best seen in FIG. 7.During a printing stroke, as the printing frame 22 is depressed,

the printing device is progressively swung into the clearance positionas exemplified in FIGS. 8, 9 and 10. For this purpose, the control slots65 shift from the generally centered relation to the shaft 31 as shownin FIG. 7, to an angular relatively short section 67 of the controlslots nearest the pivots 66, as shown in FIG. 8 and FIG. 9, and then inthe last part of the stroke the shaft 67 moves downwardly along themajor length of the slots 65 which is substantially parallel to theadjacent free edge of the respective side plates, as shown in FIG. 10.This provides a smooth, minimum reaction driving relationship betweenthe side plates 52 and the shaft 67 such that operation is virtuallyresistance-free and with minimum liability to wear on the shaft 67 oralong the edges defining the slots 65. In the clearance position easyaccess to the ink pad is available since the latched edge of thesupporting panel 59 is uppermost and the hinge rod 53 is lowermost sothat by swinging the panel 59 into the open position, the ink pad 55 isexposed outwardly and upwardly in convenient freely accessible relationfor inking.

In order to assure a square-on engagement of the inking pad 55 with thecharacters to be inked, positive stop means are provided on the sideplates 52 engageable with the side bars 17. In a desirable form, thestop means comprise stop lugs 65 integral with and deformed from thelongitudinal margins of the plates which are adjacent to the rod 54, andwith the lugs adjacent to the rod connections so as to be spaced towardthe rods relative to the pivots 64. Dimensions of the stop lugs 66 aresuch that when the inking device 51 has been swung into the inkingposition by action of the contact with the adjacent edges of the framebars 17 substantially as the inking pad is parallel to the faces of theprinting characters in printing position. This assures uniform inking.

To relieve the stop lugs 66 from undue impact wear, especially in therapid operation of the hand stamp, supplementary stop means areprovided. Desirably such stop means are on the frames 15 and 22 andconstructed and arranged to limit retraction movement in the returnstroke of the printing frame 22 substantially coincident with stoppingengagement of the lugs with the frame bars 17. In a durable andefficient construction, such stop means comprise respective stop lugs 69struck inwardly from and integral with the frame legs 23 spaced aboveand in general vertical alignment with the guide studs 36 and adapted toproject in free clearance relation into the slots 32. For maximumefiiciency, the stop lugs 69 are of a rounded or arcuate crown form asbest seen in FIG. 2 so as to engage in the arcuate upper terminus of therespective slots 32 (FIG. 3). This provides maximum contact area, andinertia absorption ability.

From the foregoing it will be apparent that the hand stamp of thepresent invention is direct and smooth in operation, has a minimum ofrelatively moving parts, wear pressure points are virtually eliminatedon the relatively acting elements of the construction. Adjustments ofthe character bands is not only facilitated but proper alignment andmaintenance of alignment of the printing characters is assured.Self-inking is greatly improved together with utmost facility andconvenience in supplying the ink pad with ink by merely swinging downthe carrying panel as shown in FIG. 11 when the inking device is in theclearance position demonstrated in FIG. 10. Overall length of the handstamp is maintained minimal by the unique manner in which the inkingdevice swings the ink pad in underhand relation to the printing unit andin the printing stroke clears the inking pad in an arcuate pathoutwardly and upwardly into a position alongside and clear of thedepressed printing unit with the slot terminus shoulder.

Not only is efficient indexing of the character bands enabled but wherefor any reason there is any longitudinal misalignment of a character atthe thrust bar, automatic self-alignment or adjustment occurs as theprinter is used, so that proper alignment of the characters in printingposition is always assured.

It will be understood that variations and modifications may be effectedwithout departing from the spirit and scope of the novel concepts ofthis invention.

We claim:

1. A hand stamp assembly comprising an upright body frame having matchedelongated slots including a base to be thrustingly engaged with anobject to be imprinted, a printing frame, a printing unit within thebody frame and operatively coupled with said printing frame by means ofconnecting means from the printing unit to the printing frame riding insaid slots, said printing unit having character-carrying means movableto shift different printing characters thereon into printing positionfacing toward said base, and means normally biasing the printing frameand thereby the printing unit into a retracted position on the bodyframe away from said base and from which position the printing frame canbe moved in opposition to the biasing means to drive the printingcharacters into imprinting engagement with an object against which thebase is thrustingly engaged, including:

a self-inking device comprising a carriage having side plates pivotallyattached within said body frame and printing frame and carrying aninking pad therebetween; said plates having matching control cam slotstherein; said connecting means being operatively engaged in said camslots and said elongated slots to effect swinging of the carriagebetween a position wherein the inking pad is in inking contact with theprinting characters which are in printing position in a retractedrelation of the printing frame and the printing unit relative to saidframe and base, and a clearance position relative to said printing frameand the printing unit wherein the inking pad is located at one side ofthe body frame to permit movement of the printing frame and the printingunit in opposition to said biasing means and relative to said body frameto effect imprinting by the inked printing characters upon an objectagainst which the base is thrust.

2. An assembly according to claim 1, wherein said body frame includesstop surfaces, and stop lug means on said plates of the carriageengageable with said stop surfaces to assure proper registration of theink pad with the printing characters.

3. An assembly according to claim 2 having stop lugs projecting fromsaid printing frame into said longitudinal slots and engageable with astop surface provided at an end of said slots in the retracted positionof the printing frame, said engagement of the carriage plate lugs withthe body frame stop surfaces and engagement of the printing frame lugswith said slot end stop surfaces being coordinated to relieve the stoplugs on the carriage plates from undue impact wear.

4. An assembly according to claim 1, wherein said body frame comprisesspaced vertical bars and said printing frame comprises spaced verticallegs reciprocably movably positioned along the outer sides of said framebars, said frame bars having said matched longitudinal slots therein,and said printing frame legs having lugs thereon projecting into saidslots, said slots having end stop surfaces engaged by said lugs in theretracted position of the printing frame.

5. An assembly according to claim 4, including a shaft pin connectingsaid printing head with said printing frame legs and extending throughsaid vertical slots spaced from said lugs, and studs carried by saidlegs and extending through said longitudinal slots intermediate saidshaft pin and said lugs and engaging with means on said printing unitand cooperating with said shaft pin to hold the printing unit in stable,vertical, centered working relation within the body frame, said shaftpin extending through said cam slots in the inking carriage plates andcomprising said coupling means.

6. An assembly according to claim 1, wherein said character-carryingmeans comprise a yieldable band having a series of printing charactersthereon, said printing unit including a transverse rigid thrust barfacing generally toward said base and having a surface facing toward theback of said band and of a width to receive selected printingcharacter-carrying areas of the band in printing position, said surfacehaving a depression therein, and said back of the band being normallyspaced from said surface across said depression but engaging the thrustbar at opposite sides of the depression, whereby inward yielding intosaid depression of the band is permitted when the printing characters inprinting position encounter uneven, angular or tilted surfaces duringimprinting marking of an object.

7. An assembly according to claim 6, said band having on the backthereof indexing means projecting partially into said depression butremaining normally spaced from said surface within the depression exceptat the opposite sides of the depression.

8. An assembly according to claim 7, wherein said indexing meanscomprise resilient projections on the back of the band.

9. An assembly according to claim 8, said projections on the back of theband comprising transverse serration-like rib teeth, and band movingwheel means on the printing unit having complementary transverse rigidrib teeth meshing with said rib teeth on the band.

10. An assembly according to claim 9, said rib teeth on the band beingprovided in respective areas having a length substantially equal to thewidth of said depression and the back of the band being free from teethat both ends of the tooth area, whereby in the movement of the bandacross said thrust bar said teeth provide. a mild frictional resistanceto movement across the portions of the bar at opposite sides of saiddepression and immediately on passing of the tooth area from saidportions of the bar into registration with said depression there isrelief of the resistance and sensible indication that the associatedprinting character has been moved into printing position.

11. An assembly according to claim 1, said carriage including an ink padsupporting panel hingedly mounted on and between said carriage plates,and means normally latching said panel in position on said plates tosupport the ink pad for its inking function and the latching means beingreleasable for swinging the panel away from the inking position foraccess to the inking pad to supply ink thereto.

12. An assembly according to claim 11, said latching means including alatching projection on said panel, and a transverse rod secured to andbetween said panels and engageable by said latching projection.

13. An assembly according to claim 11, comprising a pair of spaced rodssecured to and between said carriage plates, said panel being hingedlyconnected to one of said rods and the latching means comprising astructure releasably engageable with snap-action with the other of saidrods.

14. An assembly according to claim 11, said panel having a tray securedthereto, and said inking pad being carried by said tray.

15. An assembly in accordance with claim 1 in which said matchedelongated slots have a shoulder at the end farthest from the base, stoplugs on the printing frame extend into said slots and engage saidshoulders to limit movement of the printing frame to said retractedposition, said connecting means from the printing unit to the printingframe comprises a shift pin secured to the printing frame at a locusspaced from said lugs, and extending through said matched elongatedslots; and studs fastened to said printing frame, intermediate saidshaft pin and said lugs, and extending through said matched elongatedslots to engagement with the printing unit.

16. An assembly according to claim 11, including a snap latch mechanismon said panel and said carriage for normally retaining the panel inplace on the carriage to hold the pad in position for inking theprinting characters.

1. A hand stamp assembly comprising an upright body frame having matchedelongated slots including a base to be thrustingly engaged with anobject to be imprinted, a printing frame, a printing unit within thebody frame and operatively coupled with said printing frame by means ofconnecting means from the printing unit to the printing frame riding insaid slots, said printing unit having character-carrying means movableto shift different printing characters thereon into printing positionfacing toward said base, and means normally biasing the printing frameand thereby the printing unit into a retracted position on the bodyframe away from said base and from which position the printing frame canbe moved in opposition to the biasing means to drive the printingcharacters into imprinting engagement with an object against which thebase is thrustingly engaged, including: a self-inking device comprisinga carriage having side plates pivotally attached within said body frameand printing frame and carrying an inking pad therebetween; said plateshaving matching control cam slots therein; said connecting means beingoperatively engaged in said cam slots and said elongated slots to effectswinging of the carriage between a position wherein the inking pad is ininking contact with the printing characters which are in printingposition in a retracted relation of the printing frame and the printingunit relative to said frame and base, and a clearance position relativeto said printiNg frame and the printing unit wherein the inking pad islocated at one side of the body frame to permit movement of the printingframe and the printing unit in opposition to said biasing means andrelative to said body frame to effect imprinting by the inked printingcharacters upon an object against which the base is thrust.
 2. Anassembly according to claim 1, wherein said body frame includes stopsurfaces, and stop lug means on said plates of the carriage engageablewith said stop surfaces to assure proper registration of the ink padwith the printing characters.
 3. An assembly according to claim 2 havingstop lugs projecting from said printing frame into said longitudinalslots and engageable with a stop surface provided at an end of saidslots in the retracted position of the printing frame, said engagementof the carriage plate lugs with the body frame stop surfaces andengagement of the printing frame lugs with said slot end stop surfacesbeing coordinated to relieve the stop lugs on the carriage plates fromundue impact wear.
 4. An assembly according to claim 1, wherein saidbody frame comprises spaced vertical bars and said printing framecomprises spaced vertical legs reciprocably movably positioned along theouter sides of said frame bars, said frame bars having said matchedlongitudinal slots therein, and said printing frame legs having lugsthereon projecting into said slots, said slots having end stop surfacesengaged by said lugs in the retracted position of the printing frame. 5.An assembly according to claim 4, including a shaft pin connecting saidprinting head with said printing frame legs and extending through saidvertical slots spaced from said lugs, and studs carried by said legs andextending through said longitudinal slots intermediate said shaft pinand said lugs and engaging with means on said printing unit andcooperating with said shaft pin to hold the printing unit in stable,vertical, centered working relation within the body frame, said shaftpin extending through said cam slots in the inking carriage plates andcomprising said coupling means.
 6. An assembly according to claim 1,wherein said character-carrying means comprise a yieldable band having aseries of printing characters thereon, said printing unit including atransverse rigid thrust bar facing generally toward said base and havinga surface facing toward the back of said band and of a width to receiveselected printing character-carrying areas of the band in printingposition, said surface having a depression therein, and said back of theband being normally spaced from said surface across said depression butengaging the thrust bar at opposite sides of the depression, wherebyinward yielding into said depression of the band is permitted when theprinting characters in printing position encounter uneven, angular ortilted surfaces during imprinting marking of an object.
 7. An assemblyaccording to claim 6, said band having on the back thereof indexingmeans projecting partially into said depression but remaining normallyspaced from said surface within the depression except at the oppositesides of the depression.
 8. An assembly according to claim 7, whereinsaid indexing means comprise resilient projections on the back of theband.
 9. An assembly according to claim 8, said projections on the backof the band comprising transverse serration-like rib teeth, and bandmoving wheel means on the printing unit having complementary transverserigid rib teeth meshing with said rib teeth on the band.
 10. An assemblyaccording to claim 9, said rib teeth on the band being provided inrespective areas having a length substantially equal to the width ofsaid depression and the back of the band being free from teeth at bothends of the tooth area, whereby in the movement of the band across saidthrust bar said teeth provide a mild frictional resistance to movementacross the portions of the bar at opposite sides of said depression andimmediately on passing of the tooTh area from said portions of the barinto registration with said depression there is relief of the resistanceand sensible indication that the associated printing character has beenmoved into printing position.
 11. An assembly according to claim 1, saidcarriage including an ink pad supporting panel hingedly mounted on andbetween said carriage plates, and means normally latching said panel inposition on said plates to support the ink pad for its inking functionand the latching means being releasable for swinging the panel away fromthe inking position for access to the inking pad to supply ink thereto.12. An assembly according to claim 11, said latching means including alatching projection on said panel, and a transverse rod secured to andbetween said panels and engageable by said latching projection.
 13. Anassembly according to claim 11, comprising a pair of spaced rods securedto and between said carriage plates, said panel being hingedly connectedto one of said rods and the latching means comprising a structurereleasably engageable with snap-action with the other of said rods. 14.An assembly according to claim 11, said panel having a tray securedthereto, and said inking pad being carried by said tray.
 15. An assemblyin accordance with claim 1 in which said matched elongated slots have ashoulder at the end farthest from the base, stop lugs on the printingframe extend into said slots and engage said shoulders to limit movementof the printing frame to said retracted position, said connecting meansfrom the printing unit to the printing frame comprises a shift pinsecured to the printing frame at a locus spaced from said lugs, andextending through said matched elongated slots; and studs fastened tosaid printing frame, intermediate said shaft pin and said lugs, andextending through said matched elongated slots to engagement with theprinting unit.
 16. An assembly according to claim 11, including a snaplatch mechanism on said panel and said carriage for normally retainingthe panel in place on the carriage to hold the pad in position forinking the printing characters.